| Year | Value | | 2022 | 3,659 | | 2021 | 3,750 | | 2020 | 3,853 | | 2019 | 3,956 | | 2018 | 4,055 | | 2017 | 4,150 | | 2016 | 4,223 | | 2015 | 4,257 | | 2014 | 4,244 | | 2013 | 4,187 | | 2012 | 4,095 | | 2011 | 3,982 | | 2010 | 3,857 | | 2009 | 3,723 | | 2008 | 3,583 | | 2007 | 3,445 | | 2006 | 3,317 | | 2005 | 3,210 | | 2004 | 3,104 | | 2003 | 2,965 | | 2002 | 2,809 | | 2001 | 2,660 | | 2000 | 2,510 | | 1999 | 2,372 | | 1998 | 2,259 | | 1997 | 2,146 | | 1996 | 2,039 | | 1995 | 1,952 | | 1994 | 1,877 | | 1993 | 1,822 | | 1992 | 1,791 | | 1991 | 1,759 | | 1990 | 1,707 | | 1989 | 1,645 | | 1988 | 1,595 | | 1987 | 1,557 | | 1986 | 1,511 | | 1985 | 1,460 | | 1984 | 1,415 | | 1983 | 1,366 | | 1982 | 1,291 | | 1981 | 1,206 | | 1980 | 1,134 | | 1979 | 1,082 | | 1978 | 1,054 | | 1977 | 1,034 | | 1976 | 998 | | 1975 | 944 | | 1974 | 891 | | 1973 | 845 | | 1972 | 824 | | 1971 | 844 | | 1970 | 893 | | 1969 | 955 | | 1968 | 1,020 | | 1967 | 1,072 | | 1966 | 1,111 | | 1965 | 1,148 | | 1964 | 1,183 | | 1963 | 1,213 | | 1962 | 1,232 | | 1961 | 1,228 | | 1960 | 1,188 |
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